Smoke-consuming furnace



3 S-heets--Sheet 3.

(No'MaeLy I M. D. LEGGETT. 4

SMOKBGONSUMING FURNAGB. 10,259,761 Patented June 20, 1882.

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UNITED STATES PATENT OFFICE.

` MOETIMEE nLEeeET-r, oE CLEVELAND, oEIo.

SMOKE-CONSUMING FURNACE.

SPECIFICATION fOrming part 0f Letters Patent N0. 259,767, dated. June 20,' 18,82.

Application tiled March 13, 1882. (No model.) v

To all whomt't may concern: l

Be it known that I, MoE'rIMEn D. LEGGE-Tir,

of Cleveland, in the county of Cuyahoga and `State of Ohio, have invented certain newV and useful Improvements in Smoke-Consuming Furnaces; and I do hereby declare the following to be a full, clear, and exact description` 'smoke-consuming furnaces for generating steam; audit consists substantially in ahopper so constructed as to perform the double function of a coking-ovennd a fuel-feeder to the furnace, and the means ot' protecting the mouth of said hopper from the excessive action of heat, and the introduction of hot air into the furnace-chamber in`such a manner as to effectually consume the smoke generated in the coking process.-

4 In the drawings, Figure l represents a longitudinal sectional view of a furnace with my improvementV attached. Fig. 2 represents a front elevation of a furnace with' the door ot the hopper partly broken away. 4 Fig. 3 represents a sectional view of the hopper attached to a portion of a furnace. Fig. 4 is a vertical sectional view taken through the line .r x in Fig.'3. Fig. 5 represents an'isometric view of the inner shell or portion of the hopper. Fig. 6 shows a sectional view of a form of abridgewall that-may be used to Vcooperate with the hopper. Fig. 7 shows a desirable method of attaching the cokinghopper to the furnacein such a manner as to deliver the coke onto the grates well away from the furnace-front, and of delivering hot air into the furnace-chamber in such a manner as to protect the mouth of the hopper from the excessive action of heat. Fig. S shows a modication of Fig. 7, so as to Y deliver hot air into the mouth of the hopper in such a mannner as to insure its bein g commingled with the gases evolved in the cokingoven just before their escape into the furnacechamber.

A represents a furnace, to the front of which y is attached the hopperB. In this form of furnace the hopperis preferably inclined and attached at the end of the furnace over the front door; but it may be placed in a vertical position and be placed directly over or in the side ofthe furnace, or it may be placed in a horizontal position, in which case 'other 'means' than gravity must be depended upon to force the fuel into the furnace. rIhis hopper consists ofan outer and inner shell. The inner shell (better shown in Fig.` 5) is preferably made of tire-clay, but may be made lof castiron or any other suitable material. rlhis inner shell should be perforated with a large p vnumber'of small holes ofproper size, say onefourth of an inch in diameter, or thereabout.

Ifintended to stand iuclined,asin the drawings, or to lie horizontal, the perforations should be more numerous on the under side; or they may be entirely omitted ou the upper side. The lower end may project just through the furnace-shelhas shown in the drawings; but it is preferable to have it pass sufficiently far into the furnace to deliver the fuel well away from 'the furnace-front. This inner shell may be of the form shown in Fig. 5, or with the corners rounded, as in Fig. et, or of any other desired form. In burningsoi't coal it will, in general,'be found desirable to have this perforated shell slightly increase in dimensions from the top to the bottom, as in ythe process of coking the coal somewhat increases in bulk and will be liable to clog if the hopper is all the wayof the same size, and especially so if it should diminish from top to bottom. The size of this inner shell of the hopper must depend entirely upon the size of the furnace and the amount of coal to be fed through it.

The outer shell of the hopper may be made of boiler-iron or any other suitable material, and thetwo shells should be so attached as to leave a free open air-space around the inner shell, or at least so much of the inner shell as it maybe found desirable to perforate.

The outer'shell should be as nearly air tight as practicable, and registers b' b` should be placed near the upper end, so asto regulate the amount of air admitted into the `air space or chamber a.

The upper end of the two shells should be as nearly as practicable in line, so that the end of both shells of the hopper may be closed by the same door, C. It is preferable that as little air as possible enter the inner shell eX- cept through the perforations, that it may be well distributed 4and restricted in quantity. I

` nace.

prefer also that the hopper should be detachably attached to the furnace, so that it may be removed to facilitate cleaning or for entering the furnace for repairs.

The operation of this device is as follows: Through the doors, just under the hopper, in the form shown in the drawings, the fire is kindled on the grates. When well burning coal is fed into the hopper until the hopper is nearly or quite full, when the door C is closed and the registers b b are opened to admit the desired amount of air. The air will then be drawn by the chimney-draft through the perforations and through the body of the coal in the hopper and to the re in the fur- By a well-known law of combustion the re will gradually work toward the source of the air by which it is supplied, and in ashort time a slow combustion will work up into the hopper nearly or quite to the top. The intensity of this combustion in the hopper will depend entirely upon the amount of air admitted through the perforations in theinner shell, and this may be controlled by the registers b l). If the right amount of air is admitted into the airchamher, it will be found to produce a bright incandescence at and near the mouth of the cokingoven, and this incandescence will gradually decrease, so that the coal at the top ot' the oven will only be heated sufficiently to draw off the lnoisture. In this manner the coal will gradually increase in temperature as it descends in the coking-oven, first giving off its moisture and then its smoke-gases, all of which must pass through the more incandescent coke near the mouth of the oven. When these gases reach the mouth of the oven they become commingled with fresh heated air, introduced as hereinafter described, when they are effectnally consumed in the furnacechamber. The coke is delivered upon the grate. bars and there consumed, and the temperature is thereby continually kept upto a degree that not only perfectly consumes the smoke, but utilizes the heat in generating steam.

Through the doors or elsewhere should be a small opening with a small door or valve, D,

to close it when not used,through which atool may be inserted to push the coke back on the grates and permit it to feed down from the hopper.

It will rarely be found necessary to open the doors of the furnace, for as the coal is coked or partially coked in the hopper there will be scarcely any tendency to form clinkers on the grates, and thus cold air and cold fuel are substantially excluded from the furnace.

It will be found that a furnace constructed with this improvement will not only burn the smoke, but will be extremely economical of fuel. Perfectcombustion and exclusion of cold air and cold fuel are essential to great economy.

lt will be found necessary to supply oxygenized air to commingle with the gases in the furnace-chamber as they emerge from the cokin g oven or hopper, inorder that they may be properly burned. This air should he so introduced as to be raised to a high temperature before reaching the furnace-chamber. To secure this the lower end of the inner shell of the hopper may be let" t unperforated for a short distance, especially on the bottom, and the chamber surrounding this unperforated portion should be partitioned ott' from the balance by a partition-wall, e; This chamber should entirely surround the lower end of the inner hopper, as shown in Fig. 7; or it lnay include only a portion of the lower end, as shown in Fig. 3,just as experience may show most etlicient. I think, however, that it is preferable that most of the air should emerge into the furnace from the lower side of the inner shell, in order to secure a more perfect commingling with the gases as they escape from the coking-oven. If the air emerges from all around the mouth of the inner shell, as shown in Fig. 7, it will tend to protect the shell from destruction by the heat. The lower part of theinner shell will be at a very high temperature, because of the eoking process inside, and this will heat the air that is introduced at this point through the register d. The bridgewall may also be so constructed as to heat a column of air that may be delivered into the burning gases at the crest of the bridgewall, as indicated in Figs. 1 and 6.

There are many other well-known methods of introducing hot air into the furnace-chamber. The method I prefer, however, is to introduce it around the mouth ofthe inner shell of the hopper, as this will both protect the mouth of the hopper and deliver the hot air where it is most needed. I also find it advantageous to placeadetlector, f, made of some refractory material, directly over the mouth of the hopper to aid in commingling the air and coalgases, to deflect the same down upon the incandescent coke, where it will more certainly be consumed, and to protect the boiler at the point where it is most exposed to excessive heat.

The inner shell of the hopper isrepresented as equally perforated on all sides. This will be proper only when the hopper or cokingoven is standing in nearly or quite a vertical position. When the coking-oven is inclined, as shown in the drawings, the coal will be most compact on the under side, and consequently more impervious to air on the under side. Hence the air will tend to nd its wa-y to the furnace through t-he looser coal on the top, and that on the lower portion will be less subjected to the coking process. To avoid this the perforations should be much more numer; ous on theunder side. If found necessary, they may be almost or entirely omitted on the upper side, when such portion may well be ineluded in the chamber to supply heated air around the mouth of the coking-oven in the furnace.

Ina furnace having my attachment, fine coal and even slack maybe used, and will in many cases be found preferable to coarser and more expensive coals.

IIO

This furnace will also be' found useful in burning anthracite or hard coal, as it will avoid opening the furnace-doors and will deliver hot burning coal into the furnace instead of cold fuel.

l. The combination, with a furnace, of a cok- 1 ing fuel feeder or hopper consisting of a solid lIO or nnperforated outer casing or shell'provided with' suitable registered air-inlets and a perforated inner casin g or fuel-holder, said outer `and inner lshells" being separatedvfrom each yother by the air-space a, substantially as and jectingfrom the furnace, and provided with the solid outer shell and the perforated inner shell and the intervening air-space, a, substantially as and for the purpose shown.

4. The combination, with a furnace, of a fuel-coking feeder or hopper having its inner or perforated shell non-perforated beyond the partition e, substantially as and for the purpose shown.

5. The combination, with a furnace, of a fuel-colcing feeder or hopper consisting of two casings or shells with an airspace separating them, the outer shell bein g non-perforated, but

.provided with suitable registered air-inlets,

and the inner shell or fuel-holder proper, having perforations in front of but not beyond a partition, e, substantiallyr as and for the purposes shown.

6.A lIn combination with a furnace, a coking fuel feeder or hopper provided with a partition, e, interposed between the inner and outer shells, and located between the perforated and non-perforated sections of the inner shell, substantially as and for the purpose shown.

7.' The combination, in a furnace, of a cokingA fuel feeder or hopper consisting of an imperforate outer casing or shell provided with suitable registered air-inlets anda perforated inner casing or shell, the 'two shells being separated' to form an intervening air-space, and a door or inlet, D, opening to the interior. ofthe furnace above its floor or grate, silbstantially as set forth.

8.V The combination, with a furnace, of a fuel-eoking feeder or hopper consisting of two shells, one within the other and separated by an air-space, the outer shell constructed to supply a predetermined amount of air to the said air-space, and the inner shell, or fuel-holder proper, perforated to admit air from said airspace to the fuel, substantially as and for the purposes shown. v

In testimony whereof Ihave signed my name to this specilication in the presence of two subscribin g witnesses.

M. D. LEGGETT.

. Witnesses:

W. ENGEL, OHAs. FRYE. 

